


mutualism

by SapphyreLily



Series: Riddles of Perennials [1]
Category: Haikyuu!!
Genre: Bird!Shirabu, Dryad!Kawanishi, Dryad!Semi, Fluff I guess, M/M, aaand once again inspired by a song, mythology AU, sort of
Language: English
Status: Completed
Published: 2017-06-10
Updated: 2017-06-10
Packaged: 2018-11-12 12:12:27
Rating: General Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 3,097
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/11161593
Author URL: https://archiveofourown.org/users/SapphyreLily/pseuds/SapphyreLily
Summary: They live too closely, with too much dependency, to be just symbiotic, to simply co-exist and benefit off each other.[Alternatively: Coming Home]





	mutualism

**Author's Note:**

> Based on [The Tengu Wall](https://www.youtube.com/watch?v=vBIWK7ddLpg) from the Guild Wars 2 OST.

The morning light filters through the branches, warming the earth slowly, casting speckles of white and yellow over the leaf litter. It hovers slowly, gliding by and touching leaf and branch, waking the inhabitants from their sleep.

A little bird hops out of the hollow of a tree, trilling his morning song. It echoes down the glades, ringing across the forest. Seconds tick by, and more and more voices join his – his fellows, awoken by the stroke of sunlight over their feathers, now rising to join the melody.

The wren hops off his branch, diving to the forest floor, searching for breakfast. As the sun wakes the birds, so it too, will wake his meal – insects, of all shapes and sizes.

A beetle crawls off a notch in a tree, an ant marches up a trunk, a spider hangs in its web, waiting for its own meal to pass by.

 _Swoop, swoop, swoop–_ He is relentless in his search and capture, and it is not long before he is full, flying lazily back to his tree.

The branches tilt towards him as he approaches, the leaves parting a tunnel for him. He dives in, banking sharply to land on the branch, chirruping his greeting.

“Morning.” The dryad straddles the branch, extending a hand to the wren. It hops closer, tilting its head, and he chuckles, twisting his hand to stroke its head. “Demanding.”

He thinks he sees it open an eye to glare at him, but pays it no mind. This bird he knows – and he knows it is easily placated with pats and the little grubs that always take root in his trunk.

“Northeast side, three metres off the ground,” he tells it. “A few hatched last night.”

This time, the bird chirps almost in offence, butting his fingers with its head. He laughs, recognising the gesture. “Right, right. Save them till they’re fatter.”

The wren chirps again, hopping onto his hand and allowing him to bring it close to his chest. He cradles the tiny bird carefully, letting it snuggle into the folds of his shirt. “You have feathers, shouldn’t you be warm enough?”

The nip to his finger doesn’t faze him, but it does make a chuckle slip out. “If you’re so bothered by the cold, then migrate like the rest of your flock.”

He wheezes as a heavier weight crashes into his lap, and then there are appendages wrapping around him, a head tucked under his chin. The newly appeared spirit mumbles sulkily, “You’re warmer than my flock,” and he has to laugh.

“You always say that,” he says fondly, stroking the silky strands of his hair, plucking a down feather or two loose. “But you’ve only spent one winter with them.”

“One winter is enough to know that you can suffocate under the weight of too many feathers.” The arms around him tighten, and he sucks in a breath as he feels the cold touch of a nose even through his shirt. “You’re a better alternative.”

“I suppose I should be glad that you’re so attached to me,” he says drily. The bird spirit huffs and tilts his head, regarding him with sharp eyes.

“Who else is going to eat the grubs that like nesting in your trunk?”

“Who else is so stupid to eat grubs off a poisonous yew?” He shoots back, but the other only narrows his eyes.

“The one who is somehow immune to the poison.”

He only has a moment to brace himself before there are lips on his, hard and sharp and oddly bitter – and he doesn’t care that the taste might be insect juice, because he’s kissing him back, hard enough to bruise.

The bird spirit pulls away first, but his hands remain where they are – one cupping his head, one wrapped around his shoulders. His eyes are bright, like those of his animal form, his head tilted just so.

Then he smiles.

“See. Still immune.”

He cracks a grin at that, diving in to kiss him once, twice, thrice more.

It doesn’t matter that he will never taste the softness of his lips – birds don’t have soft beaks, after all – or that one day he will age and die and leave him alone again.

He is the only one immune to the toxins in each of his cells, and he will gladly accept his affections.

\-----

They spend every day like that – wrapped up in each other, talking, joking, sometimes going for walks in the forest, frost and leaves crunching under bare feet.

Where one goes, the other soon follows, their quiet laughter echoing through glades.

They are the talk of the forest – of every forest. Every tree and every animal across Japan knows who they are – the yew and his wren, bitter poison dipping in their veins. They talk about how they are an anomaly, how they are, perhaps, a new breed of coexistence.

They hear these things, and they do not care.

They have their worries, their misgivings, but they will never leave each other.

They are a dance, a melody trilled through the forest. They are a soft ballet, a gentle orchestra, a display of adoration that makes many envy to see.

They are the oddest kind of love between a tree and a bird, but they are never far from each other, a symphony and a duet.

They are the legends of the forest, and everyone admires them, but keeps their distance.

(Because no matter how beautiful their relationship, the yew is poisonous, and the wren that eats his grubs can only be, too.)

\-----

They are sitting on a high branch, peering at the moon through the branches, the bird spirit nestled snugly against the dryad. Their fingers are lightly intertwined, thumbs stroking skin, but always feeling the truth beneath the glamour.

(Hard, rough bark. Silky, smooth feathers.)

(Wildly different. Worlds apart.)

(Different, different, _different_.)

“Do you think,” the bird spirit begins, “About what’s beyond the forest?”

The dryad hums a little. “I have wondered. But what’s the point? I couldn’t travel elsewhere.”

The wren squeezes his fingers, and the head resting on his collarbone shifts, breath fanning across his cheek. “I could.”

“Would you?” His voice is thick, the words suddenly tripping over themselves, unable to get out.

There is no answer, only the slide of hair across his chest.

Then, “I _could_ … I would come back, and tell you what it’s like.”

He feels like he can breathe again. “Do you want to go?”

A low hum, then silence. He wonders if he has fallen asleep, and if he should return him to his nest.

“I do.”

A soft admission, a sleepy _peep_ , and he twists in his arms to bury his face in the crook of his neck. “The city would be interesting, don’t you think?”

He cradles him gently, kissing the crown of his head, picking him up and descending. “It might be. Let me know if there are any trees there.”

“Hmm.” The bird spirit twists a little, and his concentration fades away, leaving him with a handful of sleepy wren.

He smiles and places the bird in his nest.

When morning comes, they can discuss it again.

\-----

The sun is not too high in the sky, and a little wren soars above the canopy, circling, circling, before it sets off, away from the trees. A dryad stands on the topmost branches, watching until its tiny form is out of sight.

He fingers the tiny buds on some of the branches, smiling wryly.

Spring is coming, and the other birds would be coming back.

How odd then, that his favourite bird would be the one to leave.

\-----

Flying is a wonderful thing. Soaring is even better.

He flaps his wings, gliding on an updraft, watching tall, grey things come into view, shiny sides on some of them. There are small suns all around, rising from the ground on thin trees, some of them changing from red to yellow and green.

And _people._ There are so many people.

He knows what it looks like to be human – he has a human form, after all – but it seems so very odd to be moving around in that form all the time, without concentrating to maintain it.

He alights on a thin tree with a sun-fruit, tilting his head and watching the people. They are brightly or dully coloured, with the most interesting assortment of feathers he has ever seen. Some of them are small, and some are larger; some have long feathers dripping from their heads, while some have theirs short.

He sets off again, looking for other interesting things.

There are big metallic-smelling things moving on the ground, fast, maybe faster than the panthers he has seen in other countries' forests. But they are bigger than the cats, and leave a trail of smoke as they run, and he decides that they are very odd indeed.

There are nice smells and weird smells, and noise, so much more noise than he has ever heard before. Who knew humans were so noisy?

He catches a light scent and follows it, the refreshing smell reminiscent of the forest. With every beat of his wings a speck of green grows larger, until he sees trees spread all around, a small forest in the middle of the city.

He picks a shrub to land on, pecking at a bug skittering away from him. It’s a nice snack after his long flight, and he chirps to himself, hopping along the branch to find more.

There are a few birds that pass him and the tall shrub by, but he pays them no mind. They can always approach him first, if they want to talk.

“There’s a small nest of those near my roots, if you want more.”

He startles a little, _peep_ ing angrily at the dryad peering through the leaves. The dryad shrugs and seats himself, patting the ground next to him. “You’re new around here. I wondered why you’d pick me to perch on.”

He hops closer, curious but cautious of the nice dryad. The dryad seems to smile. “You have no idea what I am, do you?”

He chirps, flying down next to him, tilting his head.

The dryad picks a fallen, half-decayed leaf from the ground, wiggling its limp body at him. “Nandina? Sacred bamboo? Poisonous plant?”

The bird is silent, its stiffening body showing its belated realisation. The dryad smiles, a little sadly. “That’s alright. Go find some non-poisonous tree to perch on. I don’t blame you.”

The bird chirps angrily, fluffing up, and then the dryad finds himself face-to-face with an annoyed spirit.

“You’re nice enough. I’m not leaving unless I want to.”

The dryad raises his brows, coughing a short laugh. “Which part of ‘poisonous' didn’t you get?”

“The part that I might get poisoned, I guess.” The bird spirit shrugs, grabbing the leaf from his hand and rolling it between his fingers.

He drops the crushed body, extending his hand. “Voilà. I’m unharmed.”

The dryad stares at him for a long, long moment, before something like shock pops his mouth open. “You’re the poison wren.”

It’s a weird name, and he isn’t sure what to think of it, but it’s almost close enough to let pass. “Poison-resistant, you mean.”

“Of course,” the dryad murmurs, eyes soft, lips tilted up. “Why are you so far from your tree?”

(Even in the city, they know who they are. The wren and the yew, always intertwined, always _together_.)

“I’m exploring for us.” It’s an easy reply, and he remembers their conversation, shaded by the haze of sleep and lit with the glow of moonlight. “My tree can’t come with me, but he wants to see the city too.”

The dryad bobs his head in understanding, a low gleam in his eye. “You know dryads can visit each other as long as one of them has a living tree, right?”

“No.”

(He is a young bird; his knowledge is sparse. And in the forest, no one speaks to him.)

(How could he have known?)

“Now you know.” The dryad reaches behind him, plucks a young leaf from his tree. “Take this to your tree. If he wants, he can visit me, and we can explore the forest and a bit of the city.”

The wren eyes the leaf warily. “Why are you being so nice to someone you just met?”

The dryad shrugs, the leaf twirling from limp fingers, an almost wistful look on his face. “From one poisonous being to another? It gets lonely, being isolated because you’re toxic. And besides, I’m a plant; I’ll outlive you. It’ll be nice to have a friend until someone decides to cut me down.”

He thinks about it – he knows that smile, those drooping shoulders, the wistfulness in every vein. He knows what it’s like to be looked upon from afar, never to be approached.

The nandina's not wrong. He knows he will die someday, and his yew will be as lonely as he was before he came along.

“I’ll take your leaf when I return to the forest.”

The dryad nods, graciously accepting, an arm sweeping out to the rest of the mini-forest. “Have fun exploring. I’ve got some bugs if you want to come back.”

They share a smile and the wren takes off, off to find new things, a promise at his back.

\-----

He doesn’t know how long he stays – but the city is exciting and foreign, and he can’t get enough of it.

Some days he wanders in the crowd, pressed up against the other humans, eyes taking in the bright colours, tasting something new on every breath. Some days the nandina dryad wanders with him, teaching him the names of human things, showing him hidden sights and sounds.

It’s beautiful and terrifying, but he falls more and more in love with it, though the greasy smells of exhaust and takoyaki stick to his feathers for far too long.

At night he roosts within a thick-growing clump of the nandina’s leaves, their changing colours the only indication that time is passing.

The city is always bustling. It never sleeps, with its lights and loud karaoke and food stalls that close too late. He could watch it forever, this pulsing entity that is at once in its own bubble, suspended in time, yet also speeding along, changing minutely and exponentially.

But some nights, he looks up at the sky, at the moon hanging in infinite space, and he feels a tug in his heart, a deep yearning to go home.

(There are no stars in the city – too much light pollution, the nandina said – and he misses them fiercely.)

(But more than that, he misses the warmth at his back, the puff of breath over the top of his head, the whispers and teasing and jostling.)

(He misses his yew, so much that sometimes, he can’t breathe.)

He keeps wondering, _when will I finally be heartsick enough to go home?_

He doesn’t know.

(But maybe he does.)

He’s wandering in Harajuku again when it happens, eyes picking out the bright colours and fun outfits, listening to the sounds of people hurrying along, and the occasional human couple bustling by.

He doesn’t know what does it, but he’d stopped in a quieter street just off the main one, hiding in the cool of a shop – and suddenly he can’t breathe, he’s holding his breath, he’s frozen and in suspended animation.

He flees the shop before he can take another breath, and in an abandoned alley sheds his glamour and takes to the skies, washing away the scent.

(The scent, the scent, the _scent_.)

(Sprigs of yew, cut and dried and leaving a pleasant smell in the air.)

(He knows.)

(It’s time to go home.)

He’s back by the nandina before long, but he’s too agitated, too nervous, too jittery. His song is stilted and broken and so, so sorrowful, and it takes the dryad physically grabbing him before he shuts up.

“Stop panicking and tell me what is the problem.”

He struggles, oh he does, the thrumming of his heart too rapid and his song desperate.

_I want to go home, I need to go home, it’s time, it’s time, I need to be home–_

The dryad forces a ripe berry into his beak to gag him, sighing when he is finally silenced. “I know you don’t eat berries, so shut up and tell me calmly what the matter is.”

He tries to breathe around the berry, but it’s not easy. But he does, calms himself enough to take on his human form, spitting the berry out and blurting, “I want to go home.”

The dryad raises his eyebrows, unfazed. “So go. But maybe after you’ve eaten, you look terrible.”

“I don’t look bad, I just feel terrible. And I really, really want to go home–”

“Shut up,” the dryad sighs. “Have a beetle for the flight. And stop panicking, it’s a weird look on you.”

He pauses his panicking to snap at him, but accepts the proffered beetle and the family of grubs and a few spiders, apprehension thrumming faintly under his skin.

_I need to go home._

\-----

He hears the call before he sees the bird – a long trill, a shrieked song – panic and joy rolled into a terrifying screech.

He laughs giddily, disbelievingly, and parts the leaves for it.

The wren dives for the branch, banking sharply and shifting midway in its land-run sequence. They almost fall off the tree when he crashes into him, but he has branches ready to catch them – not that it matters.

He’s holding fast, braced against the trunk, arms encircling the one he had been missing for almost three seasons.

_He’s back._

He buries his face in the silkiness of the other’s hair, smells the weird tinge of smoke and city smells and – another plant?

But he’s back, he’s _back_ , and nothing else matters.

The bird spirit still has his face buried in his shirt, arms wrapped tightly around him, and he can feel the shudders going through his smaller frame.

He doesn’t pry but strokes his hair, kisses his head, feels and memorises the shape of him once again.

_I’ve missed you._

_I’ve missed you, I’ve missed you, and I’m so glad you’re back._

It feels like forever, yet barely a second, before the wren looks up, a wobbly smile on his face, eyes watery. “I’m home.”

He thinks his face may split with the force of his smile, and leans in to brush their noses together.

“Welcome home.”

**Author's Note:**

> Yes, there are no names in this bc I'm pretty sure spirits don't give themselves names.
> 
> But anyway, in case you didn't get it:  
> Semi - Japanese Yew  
> Shirabu - Eurasian Wren  
> Kawanishi - Nandina/Sacred Bamboo  
> (I don't know if wrens are actually resistant to any toxins ok, just pretend Shirabu has a funny genetic quirk that makes him poison/toxin-resistant)
> 
> Also I had to decide between 'symbiosis' and 'mutualism' for the title and I've obviously been studying too much k bye


End file.
